VIPA CP 1413plus, Руководство пользователя

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Programming CP1413plus manual
7-68 Rev. 00/07
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#include <S5ACCESS.H>
USHORT WENTRY_C S5AbfrageLesenOverlapped(
S5_PARAMS W_POINTER s5,
void (WENTRY_C *UserFctCall)(S5_PARAMS W_POINTER s5),
long Timeout_ms)
The
S5AbfrageLesenOverlapped
function determines whether the data that was previously
requested by means of a
S5StarteLesenOverlapped
function is available. Internally, this
function employs the overlapped mechanism to access the function
UserFctCall
cyclically while
you are waiting for an event.
You must continue calling this function until you receive the expected data or an error message that
indicates a connection error.
Parameters
s5
pointer to a structure of the type
S5_PARAMS
. The values
Kennung, DB, DW
and
Len
of the
s5
structure must contain
valid entries.
s5
must contain a valid connection number which
was returned by the function
S5StarteVerbindung
.
The function will either return a 0 or an H1 error.
If the returned value is 0 you can access the received data as
follows:
PLCData[0]=(UCHAR*)s5+sizeof(S5_0;
PLCData[1]=(UCHAR*)s5+sizeof(S5_1;
Tab. 7-9 contains an overview of the H1 errors and their
description.
Any S5 errors returned by the other station are located in
Fehler
.
Chapter 7.6.3.4 contains an overview of the S5 error codes. A 0 in
Fehler
indicates that the data transfer was completed properly.
UserFctCall
pointer to a function located in the application program. This is
accessed at a rate of 10ms by the DLL while the function is being
processed. This mechanism returns control to your program while
the overlapped function is being executed (see chapter 7.6.1.1.2).
The User-Function must be defined as follows:
void WENTRY_C UserCallback(S5PARAMS W_POINTER
s5);
Timeout_ms
the time limit for completion of the function by the DLL (see
chapter 7.6.1.1.2). The connection will be terminated if a timeout
occurs.